1. Field of Invention
The present invention relates to a transistor array substrate, and more particularly, to a top-gate transistor array substrate.
2. Related Art
Currently, a liquid crystal display (LCD) with a metal oxide semiconductor (MOS) layer is present. The thin-film transistor (TFT) of the LCD has an active layer made of MOS. When the LCD is in operation, a positive voltage is applied to a gate of the TFT to enable the gate to generate an electric field.
A plurality of oxygen ions (O2−) in the semiconductor layer are driven by the electric field and move towards the gate. When the oxygen ions move towards the gate, an oxygen vacancy occurs in the MOS layer. That is to say, the regions lacking oxygen ions are present in the MOS layer. Once too many oxygen ions move towards the gate, the resistance of the MOS layer will change, and it influences the operation of the LCD, thereby resulting in decrease of the reliability of the LCD.